Integrated circuit or so-called "intelligent" or "smart" cards which include a microprocessor and memory are commercially available and are useful in many applications. Of increasing importance is the ability of smart cards to securely transport monetary funds, including transportation of postal funds or information relating to postage funds. See, for example, U.S. application serial no. 153396 filed Feb. 8, 1988 entitled "Postal Charge Accounting System" wherein departmental postage meter use information is stored in smart card memory, and U.S. application serial no. 153398 filed Feb 8, 1988 entitled "Postage Meter Value Card System" wherein postage meter funds are transferred from a value card center to a postage meter for recharging the postage meter vault.
Given the increasing importance of information stored in smart card memory, the adverse effects of a malfunctioning smart card can be quite costly. Therefore, it would be highly desirable to provide a smart card having increased reliability. It would also be highly desirable to provide a smart card which may be accessed by service personnel even were a card malfunction to occur. In this manner, monetary funds stored in the card would not be "lost" due to card malfunction.
Therefore, it is an object of the present invention to provide an improved smart card.
It is another object of the invention to provide a fault tolerant smart card.
It is yet another object of the invention to provide access to information retained in memory of a smart card which suffers a malfunction.
These and other highly desirable objects and advantages are obtained in a convenient yet secure fault tolerant smart card.
Objects and advantages of the invention are set forth in part herein and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.